Apparatus for controlling railway switches



Feb. 5, 1929.

H. S. LOOMIS APPAfiATUS FOR CONTROLLING RAILWAY SWITCHES INVENTOR; H-. .5, Loan-n s Filed Oct. 26, 1927 can- 4 Patented Feb. 5, 1929.

UNITED STATES 1,701,080 PATENT "OFFICE.

HAROLD S. LOOMIS, OF WILKINSBUBG, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL GOMYANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION 01' PENNSYLVANIA.

APPARATUS FOR CONTROLLING RAILWAY SWITCHES.

Application filed October 26, 1927. Serial No. 228,805.

My invention relates to apparatus for controlling railway switches, and particularly to apparatus for normally controlling a switch from a distant point, but for at times modifying such control in accordance with traffic conditions adjacent the switch.

I will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing one form of apparatus embodying my invention.

Referring to the drawing, the reference characters 1 and 1" designate the track rails of a stretch of railway track over which traiiic normally moves in. the direction indicated by the arrow. The stretch of track shown in the drawing is provided with a switch 3 of the usual and well known form. Switch 3 is operated by a motor M which in the form here shown comprises a cylinder 5 containing a reciprocable piston 6 operatively connected with the switch 3. luid under pressure, usually compressed air, is at times supplied toone end or the other of the cylinder 5 from a suitable source not shown in the drawing, and the supply of such fluid pressure is controlled by a switch valve designated in general' by the reference character K. This valve comprises a normal magnet N, a reverse magnet R, and a lock magnet L having two windings 7 and 8. As shown in the drawing, the

switch occupies its normal position. It now,

either of the windings of the lock magnet is energized and the reverse magnet R is also energized, fluid pressure will be supplied to the motor M to o erate the switch to its reverse position. en the switch occupies its reverse position, if thenormal magnet N is energized, and if either of the windings of the lock ma 'net L is also energized, the switch valve T( will supply fluid pressure to the mot-or M to restore the switch to its normal. position. One form of switch valve which will operate in the manner described is disclosed and claimed in Letters Patent of the United States, No. 1,238,888, issued on September 4, 1917, to J. P. Coleman, for railway trafiic controlling apparatus.

The reference character G designates a circuit controller operated by the switch 3 and comprising a contact 9-9 which is closed at all times except when the switch is in its extreme reverse position. The circuit controller also comprises a contact 9---9 which is closed at all times except when the switch is in its extreme normal position. The switch 3 also controls a circuit controller E comprising two contacts 10--10 and 10-10 which are arranged to be closed when the switch occupies its normal position and reverse position, respectively. Circuit controller E also comprises a contact lever 11 which is arranged to engage a fixed contact member 11* when the switch occupies its normal position. If the switch is reversed,the contact 11--l1 remains closed until the switch reaches approximately its middle position, whereupon contact 1111 opens and contact 11-1l closes, the latter contact remaining closed while the switch is completing its movement to its reverse position and after the switch reaches the latter position. The operation of the contacts 11-11"and 11-41 when the switch returns to its normal position is just the reverse of theoperation of these contacts for movement of the switch in the opposite direction and will be understood without further explanation. i

The switch valve K is controlled in part by a manually o erable lever D which may be one of a num er of similar levers embodied in an interlocking machine of the usual and well known form and which may be located in an interlocking cabin at a point remote from the switch 3. Lever 1) comprises two normal contacts l515 and 1616 and two reverse contacts 15--15 and 1616".

It is sometimes desirable, when the railway switch is to be operated from a point remote from the switch, as in the present instance, to provide apparatus for preventing operation of the switch by the lever if a train approaching the switch is within apredetermined distance of the switch. In order to accomplish this result, I provide insulated joints 2 in at least one rail of the stretch of track, to form an insulated track section AB in advance of the switch. A track but tery 4 is connected across the rails adjacent one end of the section and atrack relay G is. connected across the rails adjacent the other end or the section, the relay G operatin to modify the control of the switch valve by thedlever D when the section AB is occupie As shown in the drawing, the lever D occupies its normal position. The section A is unoccupied, and the switch 3 occupies its normal position. If the ope ator in charge of lever D Wishes to reverse the switch he reverses lever D. The closing of contact -15" completes a circuit over which our rent flows from the left-hand terminal of a battery 12, through wires 13 and 141, reverse contact 1515 of lever D, wire 17, front contact 18 of relay G, wires 19, 50 and 51, reverse magnet R, wire 20, asymmetric unit 21 and wire 22 back to the intermediate point of battery 12. Current also flows over the circuit just traced up to and including wire 50 and from Wire 50 through wire 23, winding 8 of lock magnet L, wire 2 1, contact 9---9 of circuit controller C, asymmetric unit 25 and wire 22, back to battery 12. l Vhen the circuits just traced are closed, it will be seen that current is supplied to the reverse magnet R and to winding 8 of the lock magnet L. The motor M is therefore actuated to move the switch 3 to its reverse position. During this movement of the switch contact 9-9 of circuit controller G remains closed until the switch reaches its full reverse position, whereupon this contact opens to tie-energize winding 8 of the lock magnet, L, but the reverse magnet R remains energized. When the switch attains its full reverse position, current flows from the middle point of battery 12, through wire 22, asymmetric unit 26, wire 27, contact 10-10" of circuit controller E, wires 28 and 29, front, contact 30 of relay G, wire 31, contact 16 16" of leverD, lamp 32 and wire 33 to the'righthand terminal of battery 12. The lamp 32 therefore becomes lighted to inform the operator that the switch has attained its full reverse position. If the operator wishes to restore the switch to its normal position, he returns lever D to its normal position, whereupon current flows from the left-hand terminal of battery 12, through wires 13 and 34:, normal contact 16-16 of lever D, wire 31, front contact30 of relay G, wires 29, 52 and 53 normal magnet N of switch valve K, wire 35, asymmetric unit 36, and wire 22 back to the intermediate point of battery 12. Ourrent also flows over the circuit just traced as far as wire 52 and thence through wire 37, winding 7 of lock magnet L, wire 38, contact 99 of circuit controller C, asymmetric unit 25 and wire 22 back to battery 12. The winding 7 of lock magnet L and the normal magnet N are therefore energized so that the motor M is operated to restore the switch 3 to its normal position. WVhen the switch attains its full normal position, contact 9-9 opens, deenergizing winding 7 of lock magnet L, but the normal magnet N remains energized. When the switch has attained its full normal position, current from battery 12 flows through wire 22, asymmetric unit 26,

wire 27, contact 10-10 of circuit controller E, wires 39 and 19, front contact 18 of relay Gr, wire 17, normal contact 15--15 of lever D, lamp 1O and wires 11 and 33 back to battery 12. Lamp 10 therefore becomes lighted to indicate that the switch has attained its full normal position.

It should be observed that the control circuits for both the normal and reverse opera tion of the switch as well as the normal and reverse indication circuits are carried over front contacts of the relay G. If, therefore, a train occupies section AB, so that relay G is de-energized, the switch 3 cannot be operated by the manipulation of lever D. The apparatus is arranged in such manner that if the relay G becomes de-energizcd after the operation of the lever D and before the switch has completed its movement to the corresponding position, current will be supplied over an auxiliary circuit to the switch valve to move the switch to an extreme position, thereby preventing a possibility of a train or car moving into the switch when the points of the switch occupy their intermediate positions. In explaining this feature, I will first assume that the switch lever D has been moved to the reverse position and that the motor M is operating to move the switch to its reverse position. I will also assume that the relay G becomes de-energized, as by the,

entranceof a train or car into section A-B, before the movement of the switch 3 is completed. If relay G becomes (ls-energized before contact 1111 opens, current from battery 12 will flow through wire 13, contact 11-11of circuit controller E, wire 1 1, back contact 30 of relay G, wires 29, 52 and 53, normal magnet N, wire 35, asymmetric unit 36, and wire 22 back to battery 12. Current also flows over the circuit just traced as far as wire 52 and thence through wire 37, winding 7 of lock magnet L, wire 38, contact 99" of circuit controller C, asynnnetric unit 25, and wire 22 back to battery 12. The switch will therefore be restored to its normal posit-ion unless the movement of the switch has been moved sufliciently to open contact 1111. If the de-energizatjhm of relay G occurs immediately after the opera tion of lever D and before the switch has had time to be moved away from its normal posi tion, of course contact 99 of circuit controller G will not be closed, but in this event there is no necessity for energizing the lock magnet since no movement of the switch will have occurred and hence there will be no necessity for restoring it to its original position.

If the movement of the switch has progressed so far, prior to the de-energization of relay G, that contact 1111 is closed, current from battery 12 will flow over wire 13, contact 11-11 of circuit controller E, wire 45, back contact 18 of relay G, wires 19, and 51, reverse magnet R, wire 20, asymmetric unit 21 and wire 22 back to battery 12. Under these conditions current will also flow from wire 50, through wire 23, winding 8 of lock magnet L, wire 24, contact 99 of circuit controller C, asymmetric unit and wire 22 back to battery 12. Under these conditions, it will be plain that since the lock magnet L and the reverse magnet R are both energized, the movement of the switch towards its reverse position, (which movement was initiated by the movement of lever D prior to the de-energization of relay G) will be continued and completed after the de-energization of relay G.

In similar manner, if the relay G becomes tie-energized after the operation of the lever D from its reverse to its normal position, and

before the switch has had time to attain a corresponding position, current will be supplied from battery 12 over wire 43 to restore the switch to its reverse position, or tocomplete the movement of the switch to its normal position, depending upon whether the contact 11- 11 or 111l is closed at the instant the relay G becomes (lo-energized.

Apparatus embodying my invention is particularly suitable for, though in no sense limited to, use in railway classification yards where a plurality of switches similar to switch 3 are controlled from the central interlocking cabin. It will be plain from the foregoing description that in such installations it a train or car is approaching a switch it will be impossible to move the switch away from the position which it then occupies if the train or car is in the detector section corresponding to the section AB in the drawing. If, however, the movement of the switch has been commenced before the train or car enters the detector section, the de-cnergization of the detector track relay G will cause the switch to be moved to one extreme position or the other automatically.

It should be noted that with apparatus embodying my invention the switch lever D may be operated after the relay G has become deenergized without afi'ecting the apparatus. When the train or car which caused the relay to open has left the section A-B the consequent energization of relay G will immediately restore the switch valve K to the control of the switch lever and the motor M will then be operated to move the switch to the position corresponding to the position which the lever D then occupies.

It should be pointed out that if more switches than one are to be controlled from a single point each may be supplied with apparatus similar to that here shown for operating switch 3. In this instance the wires 43 and 22 would be common to all the switches, two wires corresponding to wires 17 and 31 being required between each switch and the control station.

Although I have herein shown and described onlyone form of apparatus embodying my invention,it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is: i i

1. In combination, a railway switch, a motor for operating the switch, manually operable means for controlling the motor to move the switch to one or the other of two extreme positions, and means for at times rendering such manually operable meansineffective to control the motor and operating if the switch is in an intermediate position to actuate the motor to move the switch to an extreme position.

2. In combination, a railway switch, a motor for operating the switch, manually operable means for controlling themotor to,

move the switch to one or the other of two extreme positions, means for at times rendering said manually operable means ineffective to control the motor, and means operating at such times if and only if the switch is in an intermediate position to actuate the motor to move the switch to an extremepositiom 3. In combination, a 'ailway switch, a

motor for actuating the switch between two extreme positions, a manually operable lever, a circuit controller operated by the switch, and means for placing the motor under the control of said lever orsaid circuit controller depending upon traffic conditions adjacent the switch. 1

4. In combination, a railway switch,a relay responsive to traflic conditions adjacent the switch, manually operable means effective when the relay is energized to move the switch to one extreme position or the other. and means effective it the relay becomes deenergized when the switch is in an intermediate position to move the switch to an extreme position.

5. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by traltic conditions adjacent said switch, a manually operable lever, means effective when the relay is energized to supply current to a selected one of such magnets depending upon the position of the lever, and means effective when said relay is de=energized to supply current to a selected one of said magnets depending upon the position of the switch.

6. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by trafiic conditions adjacent said switch, a manually operable lever, a circuit controller actuated in accordance withthe position of the switch, means effective when the relay is energized to supply current to a selected one of said magnets depending upon the condition of said lever, and means effective when the relay is de-energized to supply current to a selected one of such magnets depending upon the condition of the circuit controller.

7. In combination, a switch valve comprising a normal and a reverse magnet, a railway switch controlled by said valve, a relay controlled by traffic conditions adjacent said switch, a manually operable lever having a normal and a reverse contact, a circuit controller having a first contact closed when the switch is normal and a second contact closed when the switch is reversed, a first circuit for the normal magnet including a normal con tact on the lever and a front contact 01'? the relay, a second circuit tor the normal magnet including said first contact and a back contact of the relay, a first circuit for the reverse magnet including a reverse contact on the lever and a front contact of the relay, and a second circuit for the reverse magnet including said second contact and a back contact of the relay.

8. In combination, a switch valve comprising a normal, a reverse and a two-windinglock magnet, a railway switch controlled by said switch valve, a first conductor connected with one terminal of the normal magnet and with one terminal of one winding of the lock magnet, a second conductor connected with one terminal of the reverse, magnet and with one terminal of the remaining winding of the lock magnet, a third conductor connected with the free terminals of the normal and reverse magnets, means for connecting said third conductor with the free terminal of one or the other of the windings of the lock magnet depending upon the position of the switch, a relay responsive to trafiic conditions adjacent the switch, a manually operable lever, a source of energy having one terminal connected with the third conductor, means eii'cctive when said relay is energized to connect the other terminal of the source with the first or second conductors according to the position of said lever, and means effective when said relay is de-energized to connect the free terminal of the source with the first or second. conductor depending upon the position oil the switch.

in testimony whereof I afiix my signature.

HAROLD S. LOOMIS. 

